Xinjiang Zhongtai Chemical PVC Project
Thread Content
I just returned from Xinjiang; there, internet access is not available. So I can only come back and provide everyone with an update on the projects there. I hope to get everyone’s attention and to add new information as well. The PVC project of Xinjiang Zhongtai Chemical has been launched; the manufacturer for the mixer has been basically determined, and the machine pumps are about to enter the actual construction phase. For imported pumps, Foxes has a better chance; for domestic pumps, they are likely to choose between Dainai and Deep Blue.
I’m not familiar with PVC. What special pump requires a Pumps Foß pump? Domestically, Jialite and Dalian Sulzer are both excellent pump manufacturers for API pumps.
Polyvinylchloride (PVC) – Polyvinylchloride is primarily composed of polyvinyl chloride and polyhydrogen vinyl. It has bright colors, is resistant to corrosion, and is durable. Since toxic additives such as plasticizers and anti-aging agents are used during the manufacturing process to enhance its heat resistance, toughness, and ductility, products made from PVC are generally not used for storing food or drugs. It is a synthetic material that is highly popular and widely used throughout the world today. Its global usage ranks second among various synthetic materials. According to statistics, in the year 1995 alone, the production of PVC in Europe was around 5 million tons, while its consumption was 5.3 million tons. In Germany, the production and consumption of PVC average 1.4 million tons. PVC is being produced and used worldwide at a growth rate of 4%. In recent years, PVC has seen particularly rapid growth in Southeast Asia, thanks to the urgent need for infrastructure development in the countries of that region. Among the materials that can be used to produce three-dimensional surface films, PVC is the most suitable material. PVC (polyvinyl chloride), whose monomer has the structural formula CH2=CHCl. PVC is used in a wide range of applications, mainly for making PVC cards ； PVC OEM ； PVC wire ； PVC curtains ； PVC-coated welded wire mesh ； PVC foam boards, PVC ceilings, PVC pipes, PVC baseboards, as well as wire conduits, cable insulation, plastic doors and windows, plastic bags, and more. PVC products can be found everywhere in our daily lives. PVC is used to make various leather alternatives for luggage, as well as sports products such as basketballs, soccer balls, and footballs. It can also be used to make belts for uniforms and specialized protective equipment. PVC materials have a very wide range of applications, and they possess excellent processing properties, low manufacturing costs, corrosion resistance, and insulating characteristics. Pruvin offers a wide variety of PVC cards, including regular PVC cards (calendar cards, souvenir cards, membership cards, discount cards, VIP cards, points cards, magnetic stripe cards, meal cards, scratch-off cards, smart cards, keycard access cards, gold cards, silver cards, attendance cards, etc.), matte PVC cards, transparent PVC cards, and transparent-matte PVC cards. This product features a PVC card, as it is printed using a printing machine; as a result, the card has various colors and vivid pattern effects. Priven PVC cards, rolled PVC flooring, PVC ceilings, PVC cards, PVC curtains. Analysis of factors affecting PVC market prices: The price of any commodity is ultimately determined by its supply and demand dynamics, and PVC is no exception. Factors such as upstream raw material costs, **various policies, and the macroeconomic situation all influence prices by affecting the supply and demand dynamics of PVC. 1. Impact of upstream raw materials It is now beyond doubt that the PVC industry has entered an era characterized by high costs; industry profits have been significantly compressed. Under such circumstances, the price of the product usually remains close to its production cost. Moreover, there are various production processes for PVC, and relatively speaking, the raw material costs associated with lower-cost processes have a greater impact on the price of PVC. For example, from 2005 to the first half of 2008, oil prices remained high, and the production cost of PVC via the calcium carbide method was low. Since calcium carbide was the primary raw material used in China, PVC prices did not rise in step with the prices of ethylene and crude oil. By the same logic, since the second half of 2008 to the present, due to restrictions on coal production and efforts to maintain stable prices, the cost of calcium carbide has remained high, while crude oil prices have been low. This has resulted in lower production costs for PVC produced via the ethylene method. At this time, the PVC available on the market is mainly derived from ethylene-based processes, and companies that use calcium carbide adjust their production levels according to price conditions in order to supplement the market supply. Therefore, in terms of the production costs of PVC, the main factors affecting the price should include the cost of coal, coke, electricity, calcium carbide, crude oil, ethylene, VCM, etc. Additionally, the price of raw salt also has an impact on the price of PVC to a certain extent, through the influence of chlorine’s value. (1) Coal, coke, electricity: Since industrial electricity consumption in our country still relies mainly on thermal power generation, and coke is also derived primarily from coal, the prices of these three elements are closely linked, so they are analyzed together here. Based on the production costs of PVC via the calcium carbide method, the electricity consumption per ton of polyvinyl chloride is approximately 7,000 kWh, while the coal consumption is around 3 tons. Energy costs account for over 50% of the total production costs; therefore, fluctuations in the prices of energy sources such as coal, coke, and electricity have a direct impact on the market price of PVC. At present, China’s coal industry practices production restrictions to maintain stable prices. This not only provides support for the production costs of PVC produced via the calcium carbide method in China, but it may also lead some companies to sell coal raw materials directly, rather than processing them further into PVC before selling it. As a result, the supply of PVC produced by this method is affected, which in turn raises PVC prices until they reach a reasonable level. (2) Crude oil, ethylene, vinyl chloride, dichloroethane: Globally, PVC production still relies primarily on the ethylene method. In China, however, the calcium carbide method is predominantly used; this is due, firstly, to the low costs associated with this method in the past, and Secondly, to anti-dumping measures imposed on imported PVC as well as high prices for crude oil. Now, as crude oil prices decline and the expiration of China’s anti-dumping measures takes effect, imported materials have begun to impact the domestic market. Although, thanks to the efforts of relevant associations, the implementation of anti-dumping measures on PVC imports in our country was postponed by one year, the continuous low levels of crude oil prices below $50 meant that even after imposing high anti-dumping taxes on imported materials, a significant amount of such materials continued to flow into the Chinese market. According to statistics, PVC imported in December 2008 accounted for 70% of the total annual imports. Therefore, the prices of crude oil, ethylene, as well as imported vinyl chloride (VCM) and dichloroethane (EDC), also directly influence the price trend of PVC. Furthermore, since our country imposes anti-dumping measures only on imported PVC, but does not have any protective policies in place for VCM and EDC, some domestic PVC manufacturers may directly import large quantities of VCM from abroad at low prices to use in the production of PVC. As a result, the prices of raw materials and downstream products such as VCM have a direct impact on the price of PVC in the domestic market. (3) Raw salt: The main area of consumption for raw salt is the production of chlor-alkali products. The chlorine produced through the electrolysis of raw salt is used in the manufacture of PVC and other chlorine-based products, while the sodium is used to produce soda ash and caustic soda. Although chlorine is not a major factor in the production cost of PVC, the sodium component constitutes the main cost of caustic soda and soda ash. Therefore, the price of raw salt directly affects the price of alkali products as well as market demand for them. There is a chlor-alkali balance issue between PVC and alkalis, which indirectly influences the supply of PVC and thus its price trend. 2. Factors affecting downstream demand for PVC (1) Real estate industry Given the current stage of development in this industry, PVC has entered a mature phase characterized by a clear buyer’s market. As a result, downstream demand plays a particularly important role in determining commodity prices at this stage. The largest areas of PVC consumption are profiles, shaped profiles, and pipes, which are primarily used in the construction industry. Therefore, the future development of the domestic real estate market will play a decisive role in determining the demand for PVC. Furthermore, our country is currently in the process of rural urbanization, and some investments in infrastructure can also contribute to increased demand for PVC. However, since developed countries abroad have already gone through this process and their demand for PVC is essentially saturated, coupled with the spread of the financial crisis and a decline in purchasing power in the international market, as well as the real estate industry being at a low point in its cycle, it is possible that large amounts of imported PVC will flow into the domestic market, which could have an impact on domestic prices. (2) Domestic economic trends Existing data show that the growth rate of GDP acts as a strong support for PVC prices; therefore, future domestic economic trends will have a direct impact on PVC prices. To cope with the impact of the international financial crisis, our country implemented an economic stimulus plan worth 4 trillion yuan, aimed at ensuring domestic economic growth; this funding was primarily directed toward infrastructure and agricultural development, which could boost the domestic demand for PVC. (3) Export of plastic products In addition to profiles and pipes, PVC is also widely used in plastic containers, packaging for toys and other products, as well as in daily items such as rubber shoes, shoe soles, raincoats, and sports equipment. According to statistics, China exports 6.8 billion pairs of shoes each year, and 50% of home appliances are intended for export; the export volume of these plastic products also has a certain impact on the demand for PVC. 3. **Impact of Policies (1) Petrochemical Industry Revitalization Plan At present, *** has reviewed and approved in principle the plan for the revitalization and restructuring of the petrochemical and light industry sectors. It has been decided to increase credit support for petrochemical enterprises, to suspend the approval of coal-based chemical projects such as those aimed at simply expanding production capacity, and to accelerate structural adjustments and optimize the industrial layout. Due to the restrictions on coal-based chemical industries and the support for the crude oil and petrochemical sector, it is said that large-scale ethylene production projects with capacities of 600,000–800,000 tons will come online, which could have an impact on China’s PVC production structure and thus alter the current pricing mechanism for PVC. (2) Industry entry requirements for energy conservation and emission reduction Energy conservation and emission reduction have always been of top priority in China’s development efforts. The PVC industry is a typical high-energy-consuming sector; in order to optimize the industrial structure, China has introduced new entry requirements for the chlor-alkali industry, setting maximum energy consumption limits and minimum energy efficiency standards for 22 high-energy-consuming products. Calcium carbide, PVC, caustic soda, and others fall within these regulatory frameworks, which will affect the supply of PVC over a certain period of time. In addition, the Energy Conservation Law also sets regulations regarding energy efficiency in buildings. Statistics show that PVC plays an important role in improving the energy efficiency of window frames in Europe, helping households save 1 billion euros in heating costs each year. Therefore, as energy conservation efforts in our country progress, there is likely to be an increasing demand for PVC-based energy-efficient window frames in the future. (3) Export tax rebates and export restrictions on processed trade In 2007, China reduced the export tax rebate rate for PVC from 11% to 5%. Since China’s PVC exports rely on price advantages, the reduction in export tax rebates along with export restrictions on processed trade will further narrow the profit margins of exported products, diminish the enthusiasm of PVC manufacturers to export, and exacerbate the situation of oversupply of PVC in China – especially among those companies that produce PVC by importing VCM and EDC and then reprocessing it for export. (4) Anti-dumping policies The impact of anti-dumping policies on the price trends of PVC in China can be explained from two aspects. First, China implements anti-dumping policies against PVC imported from countries such as South Korea, Japan, the United States, and Russia, preventing such imports by imposing high anti-dumping duties; this helps to stabilize the domestic supply structure of PVC during certain historical periods ； Furthermore, the situation of an oversupply of PVC in our country is extremely severe at present; the operating rate is continuously declining, and the country is shifting from a net importer to an exporter. However, other countries may impose anti-dumping measures on PVC exported by our country in order to protect their own industries, such as the special protection policies in India and Turkey. This will undoubtedly hinder China’s PVC exports and thus affect the domestic supply and demand balance. 4. Impact of products in other related fields (1) Impact on the soda ash industry In China, PVC production is primarily carried out using the calcium carbide method. Along with PVC production, an equal amount of soda ash is usually produced as well. When demand for PVC is low and production capacity is underutilized, the output of soda ash also decreases, thereby altering the supply and demand balance for this substance. By the same logic, the price of alkalis and the demand for them driven by economic development also have an impact on the supply of PVC. (2) Impact on the refining industry The entire refining industry is a systematic process; while producing finished products such as gasoline and diesel, it also generates chemical raw materials like ethylene. Therefore, if economic downturns lead to a decrease in demand for these finished products, it will also result in lower production of ethylene, thereby affecting the supply of PVC produced via the ethylene method. Chemical and physical properties: Rigid PVC is one of the most widely used plastic materials. The melting temperature of PVC during processing is a very important process parameter; if this parameter is not set correctly, it can lead to the decomposition of the material. PVC has quite poor flow properties, and its process window is very narrow. In particular, PVC materials with high molecular weights are more difficult to process (lubricants are usually added to such materials to improve their flow properties); therefore, PVC materials with low molecular weights are generally used. The shrinkage rate of PVC is quite low, generally ranging from 0.2 to 0.6%. Injection molding process conditions: Drying treatment: Drying treatment is usually not required. Melting temperature: 185–205°C. Molding temperature: 20–50°C. Injection pressure: can reach up to 1500 bar. Holding pressure: can reach up to 1000 bar. Injection speed: A suitable injection speed should be used to avoid material degradation. Flow channels and gates: All conventional gates can be used. When machining smaller parts, it is best to use a needle-point gate or a submersion gate ； For thicker components, it is best to use a fan gate. The minimum diameter of a pin-point gate or submersion gate should be 1 mm ； The thickness of the fan-shaped gate must not be less than 1 mm. Typical applications: Polyvinyl chloride boasts notable advantages such as an abundant supply of raw materials (oil, limestone, coke, table salt, and natural gas), a mature manufacturing process, low cost, and a wide range of applications. It has now become the second most widely used general-purpose resin in the world, after polyethylene resin, accounting for 29% of the global total consumption of synthetic resins. Polyvinyl chloride is easy to process and can be processed by methods such as molding, laminating, injection molding, extrusion, calendering, and blow molding into hollow forms. Polyvinyl chloride is primarily used to produce plastic soft products such as artificial leather, films, and wire insulation; it is also used for water supply pipes, household plumbing fixtures, wall panels for buildings, casings for commercial machinery, packaging for electronic products, medical devices, and fenders for speedboats. Additionally, it can be used to manufacture plastic hard products such as sheets, doors, windows, and valves. PVC can be divided into rigid PVC and soft PVC. Of this, rigid PVC accounts for about 2/3 of the market, while soft PVC accounts for 1/3. Soft PVC is generally used for floors, ceilings, and the surface layers of leather. However, because soft PVC contains softeners (which is what distinguishes it from hard PVC), it tends to become brittle and is not easy to store, which limits its range of applications. Rigid PVC contains no softeners, which gives it good flexibility, makes it easy to shape, reduces its tendency to break, and ensures it is non-toxic and pollution-free; it also has a long shelf life. Therefore, it holds great potential for development and application. Hereinafter, it will be referred to as PVC. Soft PVC is often used to make vacuum forming films, which are employed for the surface packaging of various panels; hence it is also known as decorative film or adhesive film. It is used in many industries such as construction materials, packaging, and pharmaceuticals. Among them, the building materials industry accounts for the largest share, at 60%, followed by the packaging industry, along with several other industries with limited applications. Simply put, an aqueous salt solution undergoes chemical decomposition under the influence of an electric current. This process produces chlorine, sodium hydroxide, and hydrogen. Refining, cracking petroleum or gasoline can produce ethylene. When chlorine and ethylene are mixed, dichloroethylene is produced ； Dichloroethylene can also be converted to vinyl chloride, which is a fundamental component of polyvinyl chloride. The polymerization process joins vinyl chloride molecules together to form polyvinyl chloride chains. Polyvinyl chloride produced in this way appears as a white powder. It cannot be used on its own, but it can be mixed with other ingredients to create many products. Vinyl chloride was first synthesized in 1835 in Justus von Liebig’s laboratory. Polyvinyl chloride was synthesized by Baumann in 1872. However, the first commercial product made of polyvinyl chloride was produced in the United States not until the 1920s, and it was not until the following 20 years that large-scale production began in Europe. Polyvinyl chloride has the advantages of flame retardancy (with a flame retardance value of over 40), high chemical resistance (resistant to concentrated hydrochloric acid, 90% sulfuric acid, 60% nitric acid, and 20% sodium hydroxide), good mechanical strength, and excellent electrical insulation properties. However, its heat resistance is poor; its softening point is 80°C, and it begins to decompose and change color at 130°C, with HCI being released. Properties and molding characteristics of PVC: Specific gravity: 1.38 grams/cubic centimeter; molding shrinkage rate: 0.6–1.5%; molding temperature: 160–190°C. Features: Excellent mechanical and electrical properties, high resistance to acids and alkalis, good chemical stability; however, it has a low softening point. It is suitable for use in manufacturing thin sheets, insulation layers for wires and cables, seals, etc.
Molding characteristics:
1. It is an amorphous material with low moisture absorption but poor flowability. To improve flowability and prevent the formation of bubbles, the plastic can be dried in advance. The gating system in the mold should be thick and short, with a large cross-section at the gate, and there should be no dead corners. The mold must be cooled, with its surface coated in chromium.
2. Due to its corrosive nature and poor flowability, it is best to use specialized equipment and molds. All products must have various types and amounts of additives added as required. 3. It decomposes very easily; it decomposes even more readily when in contact with steel or copper at a temperature of 200 degrees. Corrosive and irritating gases are released during decomposition, and its suitable processing temperature range is narrow. 4. When using a screw-type injection molding machine nozzle, the aperture should be large to prevent material from accumulating in dead corners. It is better to avoid using inserts; if inserts are used, they should be preheated. What are the pollutants associated with PVC? Causes of PVC pollution: Some toxic additives and plasticizers present in PVC can seep out or vaporize; certain additives can interfere with the body’s endocrine system (affecting reproductive functions), while others may increase the risk of cancer. Burning PVC waste generates carcinogenic dioxins that contaminate the atmosphere. Conventional PVC materials, such as wires and cables, are quite serious sources of pollution. During manufacturing, use, and disposal, large amounts of harmful substances such as dioxins, hydrochloric acid, and lead are generated ； When PVC material burns, it produces a large amount of smoke as well as harmful HCl gas ； Moreover, most PVC materials contain various harmful heavy metals such as Pb (lead) and Cd (cadmium), which are used as cable stabilizers, and can pose certain risks to human health ； After burning or burying, it causes pollution to the soil and water sources. Since most disposable medical device products are made of medical-grade polyvinyl chloride (PVC) or polycarbonate (PC), the thermal decomposition products generated during PVC processing are highly corrosive to steel. PC, on the other hand, has high hardness and high viscosity; therefore, the materials used for the plasticized components must be resistant to corrosion and wear, as well as possess good polishing properties. Currently, most medical injection molding machines use hard chromium plating on the barrel screws, or employ stainless steel as the material for these screws, in order to meet the aforementioned special requirements. Furthermore, to prevent the generation of gases due to thermal decomposition during PVC processing, it is necessary to coat the surfaces of the moving and fixed templates with aluminum; the surrounding sheet metal should also be coated with aluminum or made of stainless steel. The seams in the sheet metal are sealed using non-toxic silicone, so as to prevent the gases produced during plastic processing from escaping outside (the gases generated during plastic processing can be collected using specialized equipment, purified, and then released into the atmosphere). Harm of DEHP, a common additive in PVC: Since DEHP (phthalate diester) tends to aerosolize, other vinyl products such as those used inside cars, shower curtains, or flooring materials can also release toxic gases into the atmosphere. Moreover, DEHP is readily soluble in oily liquids. Additionally, there is growing concern regarding the safety issue of additives leaching out if children chew on these soft plastic toys. Some studies suggest that this additive may complicate health issues, but further research is needed. According to some medical studies, PVC plasticizers may cause chronic diseases such as scleroderma, cholangiocarcinoma, angiosarcoma, brain cancer, and acrosteolysis. In 2004, a research team composed of scholars from Sweden and Denmark discovered that the phthalates DEHP and BBzP, which are commonly used in PVC, have a strong association with childhood allergies. In the case of unplasticized polyvinyl chloride (U-PVC), there is no DEHP leaching due to the absence of plasticizers. However, stabilizers are usually added during the processing stage; most of these are lead-based stabilizers. Lead is a toxic substance that can leach out during use, posing a threat to human health and therefore cannot be ignored. Non-lead based stabilizers do exist, but they are expensive and not yet widely used. The development of China’s PVC market: In recent years, China’s PVC industry has seen remarkable growth, with numerous new and expanded production facilities coming online, resulting in a rapid increase in production capacity and output. From 1997 to 2006, the average annual growth rates for China’s PVC production capacity and output were as high as 22.2% and 20.0%, respectively. In 2006, the total national production of polyvinyl chloride resin was 8,238,583.86 tons ； In 2007, the total national production of polyvinyl chloride resin reached 9,716,783.63 tons ； From January to May 2008, the cumulative national production of polyvinyl chloride resin was 4,028,666.03 tons. From 2008 to 2012, global demand for polyvinyl chloride (PVC) is expected to grow at an average annual rate of 4%, with particularly rapid growth in demand in some developing ** countries. Demand for polyvinyl chloride resin in China will also maintain rapid growth, especially in the building materials sector, which has been experiencing fast growth in recent years. As the Chinese market becomes more internationalized, polyvinyl chloride resin packaging materials and pipes will have broad prospects for development in industries such as cement, fertilizers, grains, food, beverages, pharmaceuticals, detergents, and cosmetics, leading to a significant increase in demand for them ； Furthermore, the demand for polyvinyl chloride resin in the automotive, communications, and transportation sectors is also growing rapidly, indicating that there is still significant room for development in China’s polyvinyl chloride resin industry. Polyvinyl Chloride (PVC) Polyvinyl Chloride, abbreviated as PVC, is the most widely used synthetic resin material in China and the second most widely used one in the world. Thanks to its excellent flame resistance, wear resistance, chemical resistance, good mechanical properties, transparency of the resulting products, electrical insulation properties, and ease of processing, PVC has become one of the plastics with the widest range of applications. It is used extensively in industries such as manufacturing, construction, agriculture, daily life, packaging, electricity, and utilities. Along with polyethylene (PE), polypropylene (PP), polystyrene (PS), and ABS, it is considered one of the five major general-purpose resins. I. Introduction to Polyvinyl Chloride Polyvinyl chloride is a non-toxic, odorless white powder. It has high chemical stability and good plasticity. With a few organic solvents as exceptions, it can withstand hydrochloric acid at any concentration, sulfuric acid below 90%, nitric acid at 50–60%, and caustic soda below 20% at room temperature; it is also quite stable to salts ； PVC has poor thermal stability and light resistance; it begins to decompose at temperatures above 140°C, releasing hydrogen chloride (HCl) gas, which causes the PVC to change color. PVC has excellent electrical insulation properties and generally does not burn. It can burn when exposed to a flame, releasing HCl, but it goes out on its own once removed from the flame; it is a substance that is \"self-extinguishing\" and \"difficult to ignite.\" Based on these characteristics, PVC is primarily used in the production of profiles, shaped parts, pipes and fittings, sheets, films, cable sheaths, rigid or flexible tubes, blood transfusion equipment, and films. II. Classification of Polyvinyl Chloride Based on different application areas, PVC can be divided into: general-purpose PVC resin, high-molecular-weight PVC resin, and cross-linked PVC resin. General-purpose PVC resin is formed by the polymerization of vinyl chloride monomer under the action of an initiator ； High-polymerization-degree PVC resin refers to the resin synthesized by adding chain extenders to a vinyl chloride monomer polymerization system ； Cross-linked PVC resin is a resin produced by polymerizing vinyl chloride monomers in the presence of cross-linking agents that contain dienes and polyenes. Due to its simple production method and wide range of applications, general-purpose polyvinyl chloride is the type that makes up the majority of products available on the market; high-molecular-weight and cross-linked PVC resins are generally used more in specialized fields. Based on the method of obtaining vinyl chloride monomer, it can be classified into the calcium carbide method, the ethylene method, and the imported (EDC, VCM) monomer method (*the ethylene method and the imported monomer method are conventionally collectively referred to as the ethylene method). Currently, PVC is mainly produced by the ethylene method worldwide, while in China it is primarily manufactured using the calcium carbide method. Depending on the polymerization method of vinyl chloride monomer, polyvinyl chloride can be produced by the suspension method, emulsion method, bulk method, and solution method. The suspension method is the primary way of producing PVC, as it features a simple production process that is easy to control and suitable for large-scale manufacturing, as well as producing products with good suitability. On a global scale, approximately 80% of all PVC produced is manufactured using this suspension method. The bulk method does not require water or dispersants, has simple post-polymerization processing, and yields products of high purity. However, it faces challenges related to mixing and heat transfer during the polymerization process, resulting in higher production costs; it is therefore an obsolete process. Its production capacity accounts for less than 10% of the total. Currently, only Tianyuan in Yibin, Sichuan, uses this bulk method to produce PVC in China. In emulsion polymerization, water is used as the dispersion medium; the particles produced are relatively fine, but they lack good thermal stability and electrical insulation properties. This method is suitable for the production of PVC paste resins, which are primarily used in manufacturing artificial leather, impregnated gloves, window screens, rain boots, tool handles, wallpaper, floor coverings, battery separators, and toys. In China, the output of PVC paste resins accounts for less than 4% of the total PVC production. Solution polymerization is used only to produce coatings or specialty products. In the United States, the proportion of resins produced using various polymerization methods is as follows: 87.8% by suspension method, 6.4% by emulsion and microsuspension methods, 4.4% by bulk polymerization method, and 1.4% by solution method. In our country, over 90% of PVC is produced using the suspension method. III. Production Process and Cost Analysis of Polyvinyl Chloride 1. Production Process There are mainly two methods for producing PVC: one is the calcium carbide method, whose primary raw materials are calcium carbide, coal, and crude salt ； The second is the ethylene method, whose main raw material is petroleum. In the international market, PVC production is primarily carried out using the ethylene method, while in China, due to limited resources such as abundant coal, scarce oil, and limited gas, the calcium carbide method is mainly used. As of December 2007, the calcium carbide method accounted for over 70% of China’s total PVC production capacity. It is worth noting that in the production of PVC via the calcium carbide method, hydrogen chloride obtained from the electrolysis of raw salt is used to produce PVC, while the remaining sodium is used to produce caustic soda. Therefore, chlorine and alkali exist in a symbiotic relationship, and the balance between these two elements is an important factor that must be taken into account in the development of this industry. 2. Cost Analysis From the perspective of production costs, the cost differences between the two processes are significant across different economic development phases. Generally, during periods of rapid international macroeconomic growth, due to high oil prices, the production cost using the ethylene method is high, while the calcium carbide method offers a clear cost advantage ； And once the international economy enters a recession, oil prices will remain low; due to its high energy consumption, the calcium carbide method loses its cost advantage, as the prices of coal, electricity, and transportation provide support. Since 2003, international oil prices have risen sharply, increasing the costs of PVC produced via the ethylene method, while production using the calcium carbide method is less affected by these price increases. This has led to a new wave of construction of PVC production facilities using the calcium carbide method in China, resulting in a significant increase in the capacity for such production. This poses a serious challenge to PVC production via the ethylene method, with many companies in this sector operating on the verge of loss. However, with the continuous decline in crude oil prices after May 2008, the cost advantage of the ethylene method became evident, while producers using the calcium carbide method operated with minimal profits or even found it difficult to continue operating. The cost structure of the calcium carbide method mainly consists of costs for calcium carbide, hydrogen chloride, and water and electricity. **According to the standards, producing 1 ton of PVC requires 1.45–1.5 tons of calcium carbide (1.45 is generally used as a reference value, but in actual production the consumption is usually higher; only a few manufacturers manage to meet the standard). Additionally, 0.75–0.85 tons of hydrogen chloride gas are needed (0.76 is typically used as a reference value). The electricity consumption per ton is around 450–500 kW•h. There are also other expenses such as packaging costs, initiators, dispersants, water costs, and management fees, which vary depending on the manufacturer and the scale of production. Overall, the cost composition of the calcium carbide method is approximately as follows: calcium carbide accounts for 65–70%, hydrogen chloride accounts for 15%, electricity accounts for 6%, and other manufacturing costs account for 6%. A notable feature of the calcium carbide method is its high power consumption; not only is electricity required for the production of PVC, but a large amount of electricity is also needed to produce calcium carbide from coke. For example, approximately 3450 kW•h of electricity, 0.6 tons of coke, and 0.9 tons of limestone are required to produce 1 ton of calcium carbide. The main factors affecting the cost of the ethylene method include ethylene consumption, chlorine consumption, electricity consumption, processing aids, and labor costs for management. In the ethylene process, 0.5 tons of ethylene and 0.65 tons of chlorine are required to produce 1 ton of PVC, with these two materials accounting for approximately 60% of the total cost. Ethylene accounts for a major portion of the raw material costs, and its price has a significant impact on the cost of polyvinyl chloride. Although the ethylene method requires less energy compared to the calcium carbide method, its equipment investment is extremely high; as a result, equipment depreciation accounts for a large proportion of the costs. Since equipment investment is fixed, changes in the prices of ethylene and vinyl chloride are the main factors driving fluctuations in the price of PVC resin. IV. Main Applications and Industrial Chain of Polyvinyl Chloride 1. PVC Profiles Profiles represent the largest sector for PVC consumption in China, accounting for around 25% of the total PVC consumption. They are primarily used in the production of doors, windows, and energy-saving materials, and their use continues to increase significantly across the country. In developed countries, plastic doors and windows also hold the highest market share; for example, 50% in Germany, 56% in France, and 45% in the United States. 2. Polyvinyl chloride pipes Among the various polyvinyl chloride products, polyvinyl chloride pipes represent its second-largest area of use, accounting for around 20% of its total consumption. In our country, PVC pipes were developed earlier than PE and PP pipes; they come in a wide variety, have excellent performance, and are widely used, occupying an important position in the market. 3. Polyvinyl chloride film The PVC film sector accounts for the third-highest consumption of PVC, accounting for around 10%. After PVC is mixed with additives and plasticized, it is made into transparent or colored films of a specified thickness using a three-roller or four-roller calendering machine; films processed in this way are known as calendered films. Packing bags, raincoats, tablecloths, curtains, inflatable toys, etc. can also be made through cutting and heat-sealing. Wide transparent films can be used for greenhouses, plastic sheds, and mulch films. The heat-shrinking property of biaxially stretched films can be utilized for shrink packaging. 4. PVC rigid materials and sheets Stabilizers, lubricants, and fillers are added to PVC; after mixing, it can be extruded using an extruder to produce rigid pipes, shaped pipes, and corrugated pipes of various diameters, which are used as sewer pipes, drinking water pipes, electrical conduit, or stair handrails. By overlapping the rolled sheets and heat-pressing them, rigid sheets of various thicknesses can be produced. The sheets can be cut into the desired shapes, and then welded together using PVC electrodes and hot air to create various chemically resistant tanks, ducts, and containers. 5. General soft PVC products Can be extruded into hoses, cables, wires, etc., using an extruder ； By using injection molding machines in combination with various molds, plastic sandals, shoe soles, slippers, toys, automotive parts, and more can be manufactured. 6. Polyvinyl chloride packaging materials Polyvinyl chloride products are used for packaging, mainly in the form of various containers, films, and sheets. PVC containers are mainly used for producing bottled mineral water, beverages, cosmetic bottles, and PTP packaging for medicines; they are also used for packaging refined oils. PVC film can be used in co-extrusion with other polymers to produce laminates with low production costs, as well as transparent products with good barrier properties. Polyvinyl chloride films can also be used for stretch or heat-shrink packaging, to wrap mattresses, fabrics, toys, and industrial goods. 7. PVC wall panels and floors PVC wall panels are primarily used as a substitute for aluminum wall panels. In PVC floor tiles, apart from a portion of PVC resin, the remaining components are recycled materials, adhesives, fillers, and other substances; they are mainly used for flooring in airport terminals and other areas that require hard surfaces. 8. Polyvinyl chloride in daily consumer goods Luggage bags are traditional products made from polyvinyl chloride; this material is used to create various leather-like materials for use in luggage bags as well as sports items such as basketballs, soccer balls, and footballs. It can also be used to make belts for uniforms and specialized protective equipment. PVC fabrics for clothing are generally absorbent fabrics that do not require coating, such as raincoats, baby pants, faux leather jackets, and various rain boots. Polyvinyl chloride is used in many sports and entertainment products, such as toys, records, and sports equipment. Currently, there is significant growth in the production of PVC toys, which have an advantage due to their low production costs and ease of molding. PVC delivery standards: The PVC reference material is of grade SG5, first class, whose quality standards comply with the standard **“General-purpose PVC resin produced by suspension method (GB/T 5761-2006)”**. Grade A products are allowed for delivery as substitutes, and there is no grade premium or discount between Grade A and Grade B products. Polyvinyl chloride of manufacturers and brands recommended by the exchange; if the supplier can provide the documents specified in the \"Regulations on the Management of Standard Warehouse Receipts for Yellow Soybean No. 1, Yellow Soybean No. 2, Corn, Linear Low-Density Polyethylene, and Polyvinyl Chloride by the Dalian Commodity Exchange\", then quality inspection can be waived upon approval by the delivery warehouse. The qualifications and list of enterprises that recommend manufacturers and grades are determined and published by the exchange. The designated delivery warehouses for polyvinyl chloride are divided into benchmark delivery warehouses and non-benchmark delivery warehouses, which are located in Guangdong Province, Shanghai Municipality, Zhejiang Province, Jiangsu Province, and other places. The exchange may adjust the designated delivery warehouses as appropriate. The list of designated delivery warehouses and the premiums and discounts are determined and published by the exchange. Polyvinyl chloride delivery products are required to use packaging supplied by the original manufacturer or one approved by them. The packaging bag must display the trademark, product name, product standard number, net weight, name and address of the manufacturing factory, as well as the product model. The packaging material shall be a kraft paper bag lined with plastic film, a polypropylene woven bag, or a composite bag of kraft paper and polypropylene weave; it must ensure that the product remains undamaged during normal storage and transportation, and that it is not contaminated or leaks. The net weight of each bag is 25±0.2 kg, with 40 bags per ton, and there is no shortage or excess. The price of PVC packaging is included in the PVC contract price. Levels of the PVC value chain Permanent Virtual Circuit: A virtual circuit refers to a connection between two network devices; it is a logical communication path established by the OSI network layer for sending and receiving data. Networks with virtual circuit capabilities include X.25 connections, Frame Relay, and ATM networks. A Permanent Virtual Circuit (PVC) refers to a virtual circuit in which the connection between the two communicating parties appears to be a permanent one from the user’s perspective. PVC is predefined by the network manager. PVC is suitable for circuits that maintain a constant connection via routers, thereby facilitating the transmission of routing selection information in dynamic network environments. The carrier signal assigns PVCs to each user, thereby reducing network overhead and improving network performance. A permanent virtual circuit is a pre-defined connection between endpoint sites that essentially requires no setup time. In public long-distance telecommunications services such as Asynchronous Transfer Mode (ATM) or Frame Relay, customers enter into endpoint contracts for PVCs in advance with these telecommunications providers, and if they need to reconfigure the endpoints of these PVCs, they must contact the telecommunications providers.
Molding characteristics:
1. It is an amorphous material with low moisture absorption but poor flowability. To improve flowability and prevent the formation of bubbles, the plastic can be dried in advance. The gating system in the mold should be thick and short, with a large cross-section at the gate, and there should be no dead corners. The mold must be cooled, with its surface coated in chromium.
2. Due to its corrosive nature and poor flowability, it is best to use specialized equipment and molds. All products must have various types and amounts of additives added as required. 3. It decomposes very easily; it decomposes even more readily when in contact with steel or copper at a temperature of 200 degrees. Corrosive and irritating gases are released during decomposition, and its suitable processing temperature range is narrow. 4. When using a screw-type injection molding machine nozzle, the aperture should be large to prevent material from accumulating in dead corners. It is better to avoid using inserts; if inserts are used, they should be preheated. What are the pollutants associated with PVC? Causes of PVC pollution: Some toxic additives and plasticizers present in PVC can seep out or vaporize; certain additives can interfere with the body’s endocrine system (affecting reproductive functions), while others may increase the risk of cancer. Burning PVC waste generates carcinogenic dioxins that contaminate the atmosphere. Conventional PVC materials, such as wires and cables, are quite serious sources of pollution. During manufacturing, use, and disposal, large amounts of harmful substances such as dioxins, hydrochloric acid, and lead are generated ； When PVC material burns, it produces a large amount of smoke as well as harmful HCl gas ； Moreover, most PVC materials contain various harmful heavy metals such as Pb (lead) and Cd (cadmium), which are used as cable stabilizers, and can pose certain risks to human health ； After burning or burying, it causes pollution to the soil and water sources. Since most disposable medical device products are made of medical-grade polyvinyl chloride (PVC) or polycarbonate (PC), the thermal decomposition products generated during PVC processing are highly corrosive to steel. PC, on the other hand, has high hardness and high viscosity; therefore, the materials used for the plasticized components must be resistant to corrosion and wear, as well as possess good polishing properties. Currently, most medical injection molding machines use hard chromium plating on the barrel screws, or employ stainless steel as the material for these screws, in order to meet the aforementioned special requirements. Furthermore, to prevent the generation of gases due to thermal decomposition during PVC processing, it is necessary to coat the surfaces of the moving and fixed templates with aluminum; the surrounding sheet metal should also be coated with aluminum or made of stainless steel. The seams in the sheet metal are sealed using non-toxic silicone, so as to prevent the gases produced during plastic processing from escaping outside (the gases generated during plastic processing can be collected using specialized equipment, purified, and then released into the atmosphere). Harm of DEHP, a common additive in PVC: Since DEHP (phthalate diester) tends to aerosolize, other vinyl products such as those used inside cars, shower curtains, or flooring materials can also release toxic gases into the atmosphere. Moreover, DEHP is readily soluble in oily liquids. Additionally, there is growing concern regarding the safety issue of additives leaching out if children chew on these soft plastic toys. Some studies suggest that this additive may complicate health issues, but further research is needed. According to some medical studies, PVC plasticizers may cause chronic diseases such as scleroderma, cholangiocarcinoma, angiosarcoma, brain cancer, and acrosteolysis. In 2004, a research team composed of scholars from Sweden and Denmark discovered that the phthalates DEHP and BBzP, which are commonly used in PVC, have a strong association with childhood allergies. In the case of unplasticized polyvinyl chloride (U-PVC), there is no DEHP leaching due to the absence of plasticizers. However, stabilizers are usually added during the processing stage; most of these are lead-based stabilizers. Lead is a toxic substance that can leach out during use, posing a threat to human health and therefore cannot be ignored. Non-lead based stabilizers do exist, but they are expensive and not yet widely used. The development of China’s PVC market: In recent years, China’s PVC industry has seen remarkable growth, with numerous new and expanded production facilities coming online, resulting in a rapid increase in production capacity and output. From 1997 to 2006, the average annual growth rates for China’s PVC production capacity and output were as high as 22.2% and 20.0%, respectively. In 2006, the total national production of polyvinyl chloride resin was 8,238,583.86 tons ； In 2007, the total national production of polyvinyl chloride resin reached 9,716,783.63 tons ； From January to May 2008, the cumulative national production of polyvinyl chloride resin was 4,028,666.03 tons. From 2008 to 2012, global demand for polyvinyl chloride (PVC) is expected to grow at an average annual rate of 4%, with particularly rapid growth in demand in some developing ** countries. Demand for polyvinyl chloride resin in China will also maintain rapid growth, especially in the building materials sector, which has been experiencing fast growth in recent years. As the Chinese market becomes more internationalized, polyvinyl chloride resin packaging materials and pipes will have broad prospects for development in industries such as cement, fertilizers, grains, food, beverages, pharmaceuticals, detergents, and cosmetics, leading to a significant increase in demand for them ； Furthermore, the demand for polyvinyl chloride resin in the automotive, communications, and transportation sectors is also growing rapidly, indicating that there is still significant room for development in China’s polyvinyl chloride resin industry. Polyvinyl Chloride (PVC) Polyvinyl Chloride, abbreviated as PVC, is the most widely used synthetic resin material in China and the second most widely used one in the world. Thanks to its excellent flame resistance, wear resistance, chemical resistance, good mechanical properties, transparency of the resulting products, electrical insulation properties, and ease of processing, PVC has become one of the plastics with the widest range of applications. It is used extensively in industries such as manufacturing, construction, agriculture, daily life, packaging, electricity, and utilities. Along with polyethylene (PE), polypropylene (PP), polystyrene (PS), and ABS, it is considered one of the five major general-purpose resins. I. Introduction to Polyvinyl Chloride Polyvinyl chloride is a non-toxic, odorless white powder. It has high chemical stability and good plasticity. With a few organic solvents as exceptions, it can withstand hydrochloric acid at any concentration, sulfuric acid below 90%, nitric acid at 50–60%, and caustic soda below 20% at room temperature; it is also quite stable to salts ； PVC has poor thermal stability and light resistance; it begins to decompose at temperatures above 140°C, releasing hydrogen chloride (HCl) gas, which causes the PVC to change color. PVC has excellent electrical insulation properties and generally does not burn. It can burn when exposed to a flame, releasing HCl, but it goes out on its own once removed from the flame; it is a substance that is \"self-extinguishing\" and \"difficult to ignite.\" Based on these characteristics, PVC is primarily used in the production of profiles, shaped parts, pipes and fittings, sheets, films, cable sheaths, rigid or flexible tubes, blood transfusion equipment, and films. II. Classification of Polyvinyl Chloride Based on different application areas, PVC can be divided into: general-purpose PVC resin, high-molecular-weight PVC resin, and cross-linked PVC resin. General-purpose PVC resin is formed by the polymerization of vinyl chloride monomer under the action of an initiator ； High-polymerization-degree PVC resin refers to the resin synthesized by adding chain extenders to a vinyl chloride monomer polymerization system ； Cross-linked PVC resin is a resin produced by polymerizing vinyl chloride monomers in the presence of cross-linking agents that contain dienes and polyenes. Due to its simple production method and wide range of applications, general-purpose polyvinyl chloride is the type that makes up the majority of products available on the market; high-molecular-weight and cross-linked PVC resins are generally used more in specialized fields. Based on the method of obtaining vinyl chloride monomer, it can be classified into the calcium carbide method, the ethylene method, and the imported (EDC, VCM) monomer method (*the ethylene method and the imported monomer method are conventionally collectively referred to as the ethylene method). Currently, PVC is mainly produced by the ethylene method worldwide, while in China it is primarily manufactured using the calcium carbide method. Depending on the polymerization method of vinyl chloride monomer, polyvinyl chloride can be produced by the suspension method, emulsion method, bulk method, and solution method. The suspension method is the primary way of producing PVC, as it features a simple production process that is easy to control and suitable for large-scale manufacturing, as well as producing products with good suitability. On a global scale, approximately 80% of all PVC produced is manufactured using this suspension method. The bulk method does not require water or dispersants, has simple post-polymerization processing, and yields products of high purity. However, it faces challenges related to mixing and heat transfer during the polymerization process, resulting in higher production costs; it is therefore an obsolete process. Its production capacity accounts for less than 10% of the total. Currently, only Tianyuan in Yibin, Sichuan, uses this bulk method to produce PVC in China. In emulsion polymerization, water is used as the dispersion medium; the particles produced are relatively fine, but they lack good thermal stability and electrical insulation properties. This method is suitable for the production of PVC paste resins, which are primarily used in manufacturing artificial leather, impregnated gloves, window screens, rain boots, tool handles, wallpaper, floor coverings, battery separators, and toys. In China, the output of PVC paste resins accounts for less than 4% of the total PVC production. Solution polymerization is used only to produce coatings or specialty products. In the United States, the proportion of resins produced using various polymerization methods is as follows: 87.8% by suspension method, 6.4% by emulsion and microsuspension methods, 4.4% by bulk polymerization method, and 1.4% by solution method. In our country, over 90% of PVC is produced using the suspension method. III. Production Process and Cost Analysis of Polyvinyl Chloride 1. Production Process There are mainly two methods for producing PVC: one is the calcium carbide method, whose primary raw materials are calcium carbide, coal, and crude salt ； The second is the ethylene method, whose main raw material is petroleum. In the international market, PVC production is primarily carried out using the ethylene method, while in China, due to limited resources such as abundant coal, scarce oil, and limited gas, the calcium carbide method is mainly used. As of December 2007, the calcium carbide method accounted for over 70% of China’s total PVC production capacity. It is worth noting that in the production of PVC via the calcium carbide method, hydrogen chloride obtained from the electrolysis of raw salt is used to produce PVC, while the remaining sodium is used to produce caustic soda. Therefore, chlorine and alkali exist in a symbiotic relationship, and the balance between these two elements is an important factor that must be taken into account in the development of this industry. 2. Cost Analysis From the perspective of production costs, the cost differences between the two processes are significant across different economic development phases. Generally, during periods of rapid international macroeconomic growth, due to high oil prices, the production cost using the ethylene method is high, while the calcium carbide method offers a clear cost advantage ； And once the international economy enters a recession, oil prices will remain low; due to its high energy consumption, the calcium carbide method loses its cost advantage, as the prices of coal, electricity, and transportation provide support. Since 2003, international oil prices have risen sharply, increasing the costs of PVC produced via the ethylene method, while production using the calcium carbide method is less affected by these price increases. This has led to a new wave of construction of PVC production facilities using the calcium carbide method in China, resulting in a significant increase in the capacity for such production. This poses a serious challenge to PVC production via the ethylene method, with many companies in this sector operating on the verge of loss. However, with the continuous decline in crude oil prices after May 2008, the cost advantage of the ethylene method became evident, while producers using the calcium carbide method operated with minimal profits or even found it difficult to continue operating. The cost structure of the calcium carbide method mainly consists of costs for calcium carbide, hydrogen chloride, and water and electricity. **According to the standards, producing 1 ton of PVC requires 1.45–1.5 tons of calcium carbide (1.45 is generally used as a reference value, but in actual production the consumption is usually higher; only a few manufacturers manage to meet the standard). Additionally, 0.75–0.85 tons of hydrogen chloride gas are needed (0.76 is typically used as a reference value). The electricity consumption per ton is around 450–500 kW•h. There are also other expenses such as packaging costs, initiators, dispersants, water costs, and management fees, which vary depending on the manufacturer and the scale of production. Overall, the cost composition of the calcium carbide method is approximately as follows: calcium carbide accounts for 65–70%, hydrogen chloride accounts for 15%, electricity accounts for 6%, and other manufacturing costs account for 6%. A notable feature of the calcium carbide method is its high power consumption; not only is electricity required for the production of PVC, but a large amount of electricity is also needed to produce calcium carbide from coke. For example, approximately 3450 kW•h of electricity, 0.6 tons of coke, and 0.9 tons of limestone are required to produce 1 ton of calcium carbide. The main factors affecting the cost of the ethylene method include ethylene consumption, chlorine consumption, electricity consumption, processing aids, and labor costs for management. In the ethylene process, 0.5 tons of ethylene and 0.65 tons of chlorine are required to produce 1 ton of PVC, with these two materials accounting for approximately 60% of the total cost. Ethylene accounts for a major portion of the raw material costs, and its price has a significant impact on the cost of polyvinyl chloride. Although the ethylene method requires less energy compared to the calcium carbide method, its equipment investment is extremely high; as a result, equipment depreciation accounts for a large proportion of the costs. Since equipment investment is fixed, changes in the prices of ethylene and vinyl chloride are the main factors driving fluctuations in the price of PVC resin. IV. Main Applications and Industrial Chain of Polyvinyl Chloride 1. PVC Profiles Profiles represent the largest sector for PVC consumption in China, accounting for around 25% of the total PVC consumption. They are primarily used in the production of doors, windows, and energy-saving materials, and their use continues to increase significantly across the country. In developed countries, plastic doors and windows also hold the highest market share; for example, 50% in Germany, 56% in France, and 45% in the United States. 2. Polyvinyl chloride pipes Among the various polyvinyl chloride products, polyvinyl chloride pipes represent its second-largest area of use, accounting for around 20% of its total consumption. In our country, PVC pipes were developed earlier than PE and PP pipes; they come in a wide variety, have excellent performance, and are widely used, occupying an important position in the market. 3. Polyvinyl chloride film The PVC film sector accounts for the third-highest consumption of PVC, accounting for around 10%. After PVC is mixed with additives and plasticized, it is made into transparent or colored films of a specified thickness using a three-roller or four-roller calendering machine; films processed in this way are known as calendered films. Packing bags, raincoats, tablecloths, curtains, inflatable toys, etc. can also be made through cutting and heat-sealing. Wide transparent films can be used for greenhouses, plastic sheds, and mulch films. The heat-shrinking property of biaxially stretched films can be utilized for shrink packaging. 4. PVC rigid materials and sheets Stabilizers, lubricants, and fillers are added to PVC; after mixing, it can be extruded using an extruder to produce rigid pipes, shaped pipes, and corrugated pipes of various diameters, which are used as sewer pipes, drinking water pipes, electrical conduit, or stair handrails. By overlapping the rolled sheets and heat-pressing them, rigid sheets of various thicknesses can be produced. The sheets can be cut into the desired shapes, and then welded together using PVC electrodes and hot air to create various chemically resistant tanks, ducts, and containers. 5. General soft PVC products Can be extruded into hoses, cables, wires, etc., using an extruder ； By using injection molding machines in combination with various molds, plastic sandals, shoe soles, slippers, toys, automotive parts, and more can be manufactured. 6. Polyvinyl chloride packaging materials Polyvinyl chloride products are used for packaging, mainly in the form of various containers, films, and sheets. PVC containers are mainly used for producing bottled mineral water, beverages, cosmetic bottles, and PTP packaging for medicines; they are also used for packaging refined oils. PVC film can be used in co-extrusion with other polymers to produce laminates with low production costs, as well as transparent products with good barrier properties. Polyvinyl chloride films can also be used for stretch or heat-shrink packaging, to wrap mattresses, fabrics, toys, and industrial goods. 7. PVC wall panels and floors PVC wall panels are primarily used as a substitute for aluminum wall panels. In PVC floor tiles, apart from a portion of PVC resin, the remaining components are recycled materials, adhesives, fillers, and other substances; they are mainly used for flooring in airport terminals and other areas that require hard surfaces. 8. Polyvinyl chloride in daily consumer goods Luggage bags are traditional products made from polyvinyl chloride; this material is used to create various leather-like materials for use in luggage bags as well as sports items such as basketballs, soccer balls, and footballs. It can also be used to make belts for uniforms and specialized protective equipment. PVC fabrics for clothing are generally absorbent fabrics that do not require coating, such as raincoats, baby pants, faux leather jackets, and various rain boots. Polyvinyl chloride is used in many sports and entertainment products, such as toys, records, and sports equipment. Currently, there is significant growth in the production of PVC toys, which have an advantage due to their low production costs and ease of molding. PVC delivery standards: The PVC reference material is of grade SG5, first class, whose quality standards comply with the standard **“General-purpose PVC resin produced by suspension method (GB/T 5761-2006)”**. Grade A products are allowed for delivery as substitutes, and there is no grade premium or discount between Grade A and Grade B products. Polyvinyl chloride of manufacturers and brands recommended by the exchange; if the supplier can provide the documents specified in the \"Regulations on the Management of Standard Warehouse Receipts for Yellow Soybean No. 1, Yellow Soybean No. 2, Corn, Linear Low-Density Polyethylene, and Polyvinyl Chloride by the Dalian Commodity Exchange\", then quality inspection can be waived upon approval by the delivery warehouse. The qualifications and list of enterprises that recommend manufacturers and grades are determined and published by the exchange. The designated delivery warehouses for polyvinyl chloride are divided into benchmark delivery warehouses and non-benchmark delivery warehouses, which are located in Guangdong Province, Shanghai Municipality, Zhejiang Province, Jiangsu Province, and other places. The exchange may adjust the designated delivery warehouses as appropriate. The list of designated delivery warehouses and the premiums and discounts are determined and published by the exchange. Polyvinyl chloride delivery products are required to use packaging supplied by the original manufacturer or one approved by them. The packaging bag must display the trademark, product name, product standard number, net weight, name and address of the manufacturing factory, as well as the product model. The packaging material shall be a kraft paper bag lined with plastic film, a polypropylene woven bag, or a composite bag of kraft paper and polypropylene weave; it must ensure that the product remains undamaged during normal storage and transportation, and that it is not contaminated or leaks. The net weight of each bag is 25±0.2 kg, with 40 bags per ton, and there is no shortage or excess. The price of PVC packaging is included in the PVC contract price. Levels of the PVC value chain Permanent Virtual Circuit: A virtual circuit refers to a connection between two network devices; it is a logical communication path established by the OSI network layer for sending and receiving data. Networks with virtual circuit capabilities include X.25 connections, Frame Relay, and ATM networks. A Permanent Virtual Circuit (PVC) refers to a virtual circuit in which the connection between the two communicating parties appears to be a permanent one from the user’s perspective. PVC is predefined by the network manager. PVC is suitable for circuits that maintain a constant connection via routers, thereby facilitating the transmission of routing selection information in dynamic network environments. The carrier signal assigns PVCs to each user, thereby reducing network overhead and improving network performance. A permanent virtual circuit is a pre-defined connection between endpoint sites that essentially requires no setup time. In public long-distance telecommunications services such as Asynchronous Transfer Mode (ATM) or Frame Relay, customers enter into endpoint contracts for PVCs in advance with these telecommunications providers, and if they need to reconfigure the endpoints of these PVCs, they must contact the telecommunications providers.
Zhongtai Chemical is also set to produce SNG from coal, and is currently carrying out intensive research!
Huh? Synthetic natural gas? Why haven’t I heard anyone from within them talk about it? It’s still pretty early, right?